This section provides background information related to the subject disclosure, which is not necessarily prior art.
In the automotive industry, etching is used to study the movement of material in a sheet metal blank, which occurs when the sheet metal blank undergoes one or more manufacturing processes. Such manufacturing processes may include, without limitation, sheet metal stamping. A repeating pattern of geometric units is applied to the sheet metal blank when the sheet metal blank is flat and before the sheet metal blank undergoes the one or more manufacturing processes. After the one or more manufacturing processes are carried out, the repeating pattern of geometric units that have been etched on the sheet metal blank are examined for distortions and irregularities as the same visually indicate where the material of the sheet metal blank has moved (i.e. has been deformed) by the one or more manufacturing processes. Typically, such distortions and irregularities are great in areas where the sheet metal blank has been bent, compressed, or stretched by the one or more manufacturing processes. Examination of the etched sheet metal blank may occur digitally, where electronic images of the sheet metal blank are processed by a machine and/or a computer to identify and analyze distortions. From this information, stress, strain, and other values can be calculated. The accuracy of these calculations however are highly dependent upon the uniformity of the original etching. Accordingly, sheet metal blanks with etching errors (i.e. variations in the repeating pattern of geometric units) must be discarded.
Known etching processes call for the use of an etching screen, which may be for example, a laser etching screen. A print head or electrically charged roller moves over the etching screen and applies multiple geometric units to the sheet metal blank, creating an etched section. The etched section is typically much smaller than the sheet metal blank so the etching screen must be repositioned by hand many times to create a grid of etched sections that spans much if not all of the sheet metal blank. Because care must be taken to re-position the etching screen so that the repeating pattern of geometric units is uniform across the sheet metal blank, the etching process is slow, often taking approximately eight hours to etch one sheet metal blank. Additionally, due to the free-hand positioning of the etching screen on the sheet metal blank, etching errors regularly occur, requiring the operator to discard the improperly etched blank and start over. As a result, both the discarded blank and the operator's time are wasted.